| A | B |
|---|
| weathering | breaking down of rocks and other materials on the Earth's surface |
| mechanical weathering | weathering that does not make changes in the chemical makeup of rocks |
| exfoliation | breaking off curved sheets or slabs parallel to the rock's surface |
| frost action | when water gets into the rock's cracks and freezes causing rocks to break |
| root-pry | when rocks are broken apart by the growth of roots |
| landslide | large downhill movement of loose rocks and soil pulled by gravity |
| abrasion | wearing away of a substance by solid particles carried by wind, water or other forces |
| chemical weathering | weathering that involves changes in the chemical makeup of a rock |
| oxidation | process where oxygen combines chemically with another substance |
| carbonation | process where carbonic acid reacts chemically with other substances |
| stable rock | rock made of minerals that resist chemical weathering |
| residual soil | soil that remains on top of the rock from which it was formed |
| transported soil | soil that is moved away from the place it was formed |
| bedrock | layer of rock beneath the soil |
| humus | soil formed by decaying material, making it rich and good for growing (fertile) |
| pore space | space between particles of soil |
| horizon | soil layer |
| soil profile | cross sections of soil horizons |
| topsoil | soil in the "A" horizon |
| leaching | process in which water washes minerals from the topsoil down to the subsoil |
| subsoil | soil in the "B" horizon, or middle layer of the soil |
